Normally, the encoder is mounted entirely within the space between the two rings, and in this type of known solution the protective cover is usually mounted on the outside of the outer ring and bears axially on the axial surface of the outer ring itself at a very small distance from the encoder, in order to reduce the axial dimensions of a gap between the encoder and the cover which could, if large, reduce the strength of the signal produced by the rotation of the encoder and captured by a sensor which is installed on a stationary part in a position facing the encoder and outside the cover.
The electrical signals generated by the sensor as a result of the rotation of the encoder are transmitted to a processing unit mounted on the vehicle, which provides information on the speed of the wheels.
The geometric limitations imposed on the radial dimensions of the sensor by the size of the space, and the presence of a cover between the encoder and the sensor, reduce the strength of the signal received by the sensor in certain applications.
The object of the present invention is to provide a bearing unit for a vehicle wheel which enables the strength of the signal produced by the rotation of the encoder to be increased without any modification of the mounting configuration of the bearing unit.